netty,okhttp: make rpc followed by racy GOAWAY transparent-retry-able

A new RPC starts with the following steps:

1. Pick a READY transport
2. the READY transport calls `transport.newStream()`
3. the new stream calls `stream.start()`
4. `stream.start()` invokes or enqueus `writeHeaders()` (or for GET request, noop)

A racy GOAWAY could happen between 3 and 4, and by the retry spec, the RPC should be transparent-retry-able in this case. For Netty and OkHttp transport implementation, before step 4, (even if step 1, 2, and 3 excluding 4 are made atomic,) the http2-stream for the RPC is not created, so the current transparent retry logic does not apply and need fix.

Of course, if step 1, 2, and 3 including 4 are made atomic, and not with GET, there will be no such problem.

1 files changed, 4 insertions, 1 deletions

diff --git a/netty/src/main/java/io/grpc/netty/NettyClientHandler.java b/netty/src/main/java/io/grpc/netty/NettyClientHandler.java
index 92fdc06e7..b562e6237 100644
--- a/netty/src/main/java/io/grpc/netty/NettyClientHandler.java
+++ b/netty/src/main/java/io/grpc/netty/NettyClientHandler.java
@@ -459,7 +459,10 @@ class NettyClientHandler extends AbstractNettyHandler {
   private void createStream(CreateStreamCommand command, final ChannelPromise promise)
           throws Exception {
     if (lifecycleManager.getShutdownThrowable() != null) {
-      // The connection is going away, just terminate the stream now.
+      // The connection is going away (it is really the GOAWAY case),
+      // just terminate the stream now.
+      command.stream().transportReportStatus(
+          lifecycleManager.getShutdownStatus(), RpcProgress.REFUSED, true, new Metadata());
       promise.setFailure(lifecycleManager.getShutdownThrowable());
       return;
     }